Screw actuator for a legged robot

A leg assembly comprising:

• a first leg member extending along a first axis between a proximal end and a distal end, the proximal end comprising a first joint configured to couple the first leg member to a body for rotation about a second axis;
• a second leg member extending between a proximal end and a distal end, the proximal end of the second leg member coupled to the distal end of the second leg member at a second joint for rotation about third second axis;
• a motor positioned at least partially within a proximal end portion of the first leg member, wherein a rotatable shaft of the motor is aligned with the first axis, and wherein the second axis intersects the motor;
• a carrier coupled to the rotatable shaft such that rotation of the rotatable shaft causes the carrier to move along the first axis;
• and
• a link comprising a proximal end rotatably coupled to a distal end of the carrier and a distal end of the link rotatably coupled to the second leg member, wherein movement of the carrier along the first axis moves the link to cause rotation of the second leg member relative to the first leg member about the second joint.

A leg assembly comprising:

• a first leg member extending along a first axis between a proximal end and a distal end, the proximal end comprising a first joint configured to couple the first leg member to a body for rotation about a second axis;
• a second leg member extending between a proximal end and a distal end, the proximal end of the second leg member coupled to the distal end of the second leg member at a second joint for rotation about a third axis;
• a motor positioned at or adjacent to a proximal end portion of the first leg member, wherein a rotatable shaft of the motor being aligned with the first axis;
• a carrier coupled to the rotatable shaft such that rotation of the rotatable shaft causes the carrier to move along the first axis, the carrier positioned within an interior of the first leg member and a distal end of the carrier contacting an interior wall of the first leg member;
• and
• a link comprising a proximal end rotatably coupled to the distal end of the carrier and a distal end of the link rotatably coupled to the second leg member, wherein movement of the carrier along the first axis moves the link to cause rotation of the second leg member relative to the first leg member about the second joint, and wherein contact between the distal end of the carrier and the interior wall of the first leg member reacts an off-axis component of force imparted on the distal end of the carrier by the link.

A leg assembly comprising:

• a first leg member extending along a first axis between a proximal end and a distal end, the proximal end comprising a first joint configured to couple the first leg member to a body for rotation about a second axis;
• a second leg member extending between a proximal end and a distal end, the proximal end of the second leg member coupled to the distal end of the second leg member at a second joint for rotation about a third axis;
• a motor positioned at or adjacent to a proximal end portion of the first leg member, wherein a rotatable shaft of the motor is aligned with the first axis;
• a carrier coupled to the rotatable shaft such that rotation of the rotatable shaft causes the carrier to move along the second axis;
• and
• a link comprising a proximal end rotatably coupled to the distal end of the carrier and a distal end of the link rotatably coupled to the second leg member at a position that is proximally located on the second leg member relative the second joint, wherein movement of the carrier along the second axis moves the link to cause rotation of the second leg member relative to the first leg member about the second joint.